The New York City medical examiner says Ric Ocasek, the 75-year-old frontman for The Cars, died of heart disease, worsened by emphysema.
Ocasek's wife, model and actress Paulina Porizkova, posted a statement on Instagram , saying he was "recuperating very well after surgery" and that their two sons were making sure he was comfortable.
Porizkova did not say what type of surgery Ocasek was recovering from.
She says she went to bring him his Sunday morning coffee and "realised that during the night he had peacefully passed on".
The Cars chart-topping hits in the late 1970s and 80s included Just What I Needed, Shake It Up and Drive. The band was inducted last year into the Rock and Roll Hall of Fame.
Porizkova announced the couple's separation last year.
Australian Associated Press